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Full text of "Treatise On Applied Analytical Chemistry(Vol-1)"

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This chapter contains methods for the analysis of the commoner metals
and of the more important metallic alloys.

It: begins with (lie treatment of ferrous products, descriptions being
given of the. principal determinations usually made on cast-iron and malle-
able iron ; special ferrous products (special steels, term-metallic alloys)
are then considered. Subsequently, after a short account of electrolytic
analysis, the other common metals are dealt with : copper, /inc., lead,
antimony, tin, nickel, aluminium, silver and gold, and their chief alloys.
Lastly, methods are given for the identification of some of the metallic
coalings often applied to the surface of metallic objects for purposes of
embellishment or protection (gilding1, silver' plating, nickel-plating, etc.,
and oxidation).


Metallurgical iron products usually contain, in addition to iron, larger
or smaller proportions of other elements (carbon, silicon, manganese, phos-
phorus, sulphur, arsenic., etc.), which exert a profound inllnenee on the
properties. ()f these elements, the one of greatest interest is carbon, because,
although it is not always possible to make clear and exact distinctions, it
is on the carbon content and tin.: state in which it occurs combined or
otherwise that the distinction and classification of iron products are

According to the fn'rcoil-tige of ctti'litni, these products are divided into
two large classes : ctisl-iron and 'icronfjii-iroii,

The condition of the carbon determines the subdivision of cast-iron into
grey and white, the carbon being mostly free or as ^t'ti/>lrilic carbon, in the
former and in combination in the latter,

A third, intermediate type, of little importance, is mottled ctid-imn,
which is a, white cast-iron containing' nuclei of the grey form.

According to its ciirlion content, mtillt'ntilc iron is subdivided into wrought-
iron and ,s7<><7. In practice, however, the distinction between iron and
steel is based, besides, on the carbon content, on various other properties,
such as the possibility of tempering, the strength, the microscopic structure,
etc. Here, too, sharp differentiation is impossible, because the transition
from one type to the other is gradual, while the presence of small proportions

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